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| author | Vladimir Azarov <avm@intermediate-node.net> | 2024-10-01 15:47:05 +0200 |
|---|---|---|
| committer | Vladimir Azarov <avm@intermediate-node.net> | 2024-10-01 15:47:05 +0200 |
| commit | 4abab5ad6c8465a7528ccdd5f49367da05f78bbd (patch) | |
| tree | ebf009bf1376a5a223a915bc27cbbd791a1316bc /src/stdio/ungetc.c | |
Initial version
Diffstat (limited to 'src/stdio/ungetc.c')
| -rw-r--r-- | src/stdio/ungetc.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/stdio/ungetc.c b/src/stdio/ungetc.c new file mode 100644 index 0000000..bc629d4 --- /dev/null +++ b/src/stdio/ungetc.c @@ -0,0 +1,20 @@ +#include "stdio_impl.h" + +int ungetc(int c, FILE *f) +{ + if (c == EOF) return c; + + FLOCK(f); + + if (!f->rpos) __toread(f); + if (!f->rpos || f->rpos <= f->buf - UNGET) { + FUNLOCK(f); + return EOF; + } + + *--f->rpos = c; + f->flags &= ~F_EOF; + + FUNLOCK(f); + return (unsigned char)c; +} |