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| -rw-r--r-- | bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml index 6103f34f0b..badc7c0e46 100644 --- a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml +++ b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml | |||
| @@ -61,6 +61,48 @@ | |||
| 61 | </para> | 61 | </para> |
| 62 | </section> | 62 | </section> |
| 63 | 63 | ||
| 64 | <section id='line-joining'> | ||
| 65 | <title>Line Joining</title> | ||
| 66 | |||
| 67 | <para> | ||
| 68 | Outside of | ||
| 69 | <link linkend='functions'>functions</link>, BitBake joins | ||
| 70 | any line ending in a backslash character ("\") | ||
| 71 | with the following line before parsing statements. | ||
| 72 | The most common use for the "\" character is to split variable | ||
| 73 | assignments over multiple lines, as in the following example: | ||
| 74 | <literallayout class='monospaced'> | ||
| 75 | FOO = "bar \ | ||
| 76 | baz \ | ||
| 77 | qaz" | ||
| 78 | </literallayout> | ||
| 79 | Both the "\" character and the newline character | ||
| 80 | that follow it are removed when joining lines. | ||
| 81 | Thus, no newline characters end up in the value of | ||
| 82 | <filename>FOO</filename>. | ||
| 83 | </para> | ||
| 84 | |||
| 85 | <para> | ||
| 86 | Consider this additional example where the two | ||
| 87 | assignments both assign "barbaz" to | ||
| 88 | <filename>FOO</filename>: | ||
| 89 | <literallayout class='monospaced'> | ||
| 90 | FOO = "barbaz" | ||
| 91 | |||
| 92 | FOO = "bar\ | ||
| 93 | baz" | ||
| 94 | </literallayout> | ||
| 95 | <note> | ||
| 96 | BitBake does not interpret escape sequences like | ||
| 97 | "\n" in variable values. | ||
| 98 | For these to have an effect, the value must be passed | ||
| 99 | to some utility that interprets escape sequences, | ||
| 100 | such as <filename>printf</filename> or | ||
| 101 | <filename>echo -n</filename>. | ||
| 102 | </note> | ||
| 103 | </para> | ||
| 104 | </section> | ||
| 105 | |||
| 64 | <section id='variable-expansion'> | 106 | <section id='variable-expansion'> |
| 65 | <title>Variable Expansion</title> | 107 | <title>Variable Expansion</title> |
| 66 | 108 | ||
